Process for the detection of a product in the discharge of a catalytic material of a plurality of catalytic materials

Abstract

Process for the detection of a product in the discharge of a catalytic material of a plurality of catalytic materials which are exposed to a reaction gas, whereby an adsorbent selective for the product to be determined is disposed in the discharge of each catalytic material, which changes at least one of its properties through the contact with the product to be determined and the change in the property of the adsorbent is then ascertained. The process serves in particular to determine the selectivity and activity of catalytic materials.

What is claimed is:  
     
       1. Process for the detection of a product in the discharge of a catalytic material of a plurality of catalytic materials which are exposed to a common supply of a reaction gas, characterized in that the discharge of each catalytic material is fed individually to a common adsorbent, which is selective for a product to be determined, and at least one property of the common adsorbent changes through contact of the common adsorbent with the product to be determined, and at least one changed property of the adsorbent is then ascertained. 
     
     
       2. Process according to  claim 1 , characterized in that the adsorbent is a solid adsorbent or a liquid adsorbent applied to a solid carrier. 
     
     
       3. Process according to  claim 1  or  2 , characterized in that the property of the adsorbent changing through the contact with the product to be determined is an optical property. 
     
     
       4. Process according to  claim 3 , characterized in that the optical property is a color change. 
     
     
       5. Process according to  claim 1  or  2 , characterised in that the property of the adsorbent changing through the contact with the product to be determined is a fluorescence. 
     
     
       6. Process according to  claim 1  or  2 , characterised in that the property of the adsorbent changing through the contact with the product to be determined is the weight. 
     
     
       7. Process according to  claim 1  or  2 , characterised in that the property of the adsorbent changing through the contact with the product to be determined is the temperature. 
     
     
       8. Process according to  claim 2 , characterised in that the property of the liquid adsorbent changing through the contact with the product to be determined is the refractive index. 
     
     
       9. Process according to  claim 2 , characterised in that the property of the liquid adsorbent changing through the contact with the product to be determined is the pH value. 
     
     
       10. Process according to  claim 1  or  2 , characterised in that the property of the adsorbent changing through the contact with the product to be determined is the conductivity. 
     
     
       11. Process according to  claim 1  or  2 , characterized in that the product to be determined is maleic anhydride and the adsorbent is N,N-dimethylindoanyline, which is applied in ethanol solution onto a filter paper, whereby color of the adsorbent changes from blue to colorless upon contact with the maleic anhydride. 
     
     
       12. Process according to  claim 3 , characterized in that the product to be determined is maleic anhydride and the adsorbent is N,N-dimethylindoanyline, which is applied in ethanol solution onto a filter paper, whereby color of the adsorbent changes from blue to colorless upon contact with the maleic anhydride. 
     
     
       13. Process according to  claim 4 , characterized in that the product to be determined is maleic anhydride and the adsorbent is N,N-dimethylindoanyline, which is applied in ethanol solution onto a filter paper, whereby color of the adsorbent changes from blue to colorless upon contact with the maleic anhydride. 
     
     
       14. The process according to  claim 3 , wherein the optical property comprises an optical property in the infrared, visible or ultraviolet region. 
     
     
       15. The process according to  claim 4 , wherein the color change comprises emergence of a color or a decolorization. 
     
     
       16. The process according to  claim 1 , wherein said common adsorbent is spatially separated from said plurality of catalytic materials. 
     
     
       17. The process according to  claim 1 , further comprising: 
       providing support means for said plurality of catalytic materials, and wherein said support means are separate from said common adsorbent.  
     
     
       18. The process according to  claim 17 , wherein said support means comprises a porous inert substance. 
     
     
       19. The process according to  claim 1 , further comprising: 
       employing a second common adsorbent which is selective to a different product and which has at least one property that changes through contact with the different product, for simultaneous detection of the different product in the discharge of a catalytic material.  
     
     
       20. The process-according to  claim 19 , wherein said product comprises a desired product of a catalytic reaction, and said different product comprises an undesired by-product of the catalytic reaction, and further comprising: 
       determining selectivity of a catalytic material based upon detection of said product and detection of said different product.